<?php
if (! isset ( $_POST ['__EVENTTARGET'] )) {
	//---
} else {
	switch ($_POST ['__EVENTTARGET']) {
		case "edit1" :
			echo "submit1 is OK";
			break;
			
		case "edit2" :
			echo "submit2 is OK";
			break;	
		
	}
}

?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> 
<head>
<title>more submit</title>
</head>
<body>
	<form method="post" action="" name="Form1" id="Form1">
	<input type="hidden" name="__EVENTTARGET" value="" />
	<input type="hidden" name="__EVENTARGUMENT" value="" />
	<script type="text/javascript">
		function __doPostBack(eventTarget, eventArgument){
			var theform;
		  	if(window.navigator.appName.toLowerCase().indexOf("netscape") > -1){
				theform = document.forms["Form1"];
			}else{
				theform = document.Form1;
			}
			theform.__EVENTTARGET.value = eventTarget.split("$").join(":");
			theform.__EVENTARGUMENT.value = eventArgument;
			theform.submit();
		}
	</script>

<input id='change' onclick="__doPostBack('edit1','')" value="submit1" type="button" /> <input id='change' onclick="__doPostBack('edit2','')" value="submit2" type="button" /> 
</form>
</body>
</html>